1. Field of the Invention
This invention is related to self-powered electric carts and in particular to an electrically powered push-type collapsible tricycle cart having dual independent motor drive.
Electrically powered vehicles are quite popular on golf courses. However, vehicles large enough for transporting passengers are generally expensive and therefore beyond the means of the average golfer to purchase or to transport to and from the golf course. On the other hand, light pull- or push-type golf carts are known for caddying golf bags alone. Such non-powered carts are quite popular, especially if collapsible. However, a non-powdered cart becomes a major burden to drag or push around the golf course.
As a compromise, powered golf bag carrying carts have been proposed. However, such powered carts have not met with success for various reasons. A number of such problems, prior proposed solutions and shortcomings of these solutions are illustrated by the prior art.
2. Description of the Prior Art
One example of a powered golf club carrying cart is described in U.S. Pat. No. 3,704,758 to Cropp, wherein a pair of d.c. motors is series connected to a large bank of rather heavy multi-celled batteries. Such a device is costly, excessively heavy, bulky, unsightly and not easily stored or transported and therefore not readily acceptable by the average golfer. A relatively light, collapsible golf cart is therefore needed.
One proposed collapsible golf cart is described in U.S. Pat. No. 3,867,993 to Iizuka. The Iizuka patent describes a particular mechanism rendering a powered two-wheel cart collapsible. It has been found, however, that certain mechanisms of the Iizuka cart are subject to failure and frequent breakdown. For example, the legs of the Iizuka cart are subject to buckling and warping, and an internal main column slide bracket for supporting the legs is subject to jamming or sticking.
Two-wheeled carts are often found to be unsuited to power drive. Such carts with the power source (the battery) located along the main column may be easily upset if tipped too far. Prior three-wheeled arrangements, such as suggested in the Cropp patent may provide stability, but known arrangements are not suited to collapsible carts, where compact storability is a prerequisite.
It is often desirable to change the configuration of the collapsible carts slightly to accommodate the tastes of the operator or the terrain. For example, the operator may wish to raise or lower the steering arm, or it may be necessary to narrow the wheel base of the cart in order to negotiate a narrow path. It is thus desirable to include provision for adjusting steering arm height and for changing the drive wheel base without jeopardizing the performance of the cart. This might be done, for example, by assuring that the drive wheels remain parallel and vertical to the ground in cart configurations intermediate between fully collapsed and fully extended.